Well tools and methods of operating a well

ABSTRACT

Well apparatus for use in a well having a plurality of flow conductors extending thereinto and providing a crossover flow conduit and valve means for controlling flow communication between a pair of said flow conductors to permit circulation of fluids from one of said conductors to the other of said conductors by means of said crossover conduit and valve means, to move well tools into and out of the well through one or the other of said flow conductors and to circulate fluids in the well to perform well service operations, for gas lifting or aerating the fluids in said other flow conductor. A crossover device is connectable between a pair of flow conductors for establishing fluid flow communication between the flow conductors. A crossover flow control valve is removably installed in a vertical flow passage concentric with one of the flow conductors for controlling flow of fluids from said conductor to the other through the crossover passage, operable by varying the pressure in one of the flow conductors, in the well bore or in a third flow conductor in the well, operable for admitting lifting gas to the other conductor for flowing the well fluids from the well producing formation upwardly out of the well through said other conductor. A gas lift valve is mountable and removably disposable in the other conductor in communication with the crossover passage for controlling the admission of lifting gas through the crossover flow passage into the well fluid conductor for controlling the lifting of the well fluids in said conductor to the surface. The crossover flow controlling valve may be omitted, if desired, and lifting gas admitted directly from the first conductor lifting gas conductor through the crossover passage to the gas lift valve for lifting the gas in the well fluid conductor. Each valve prevents cross-flow of fluids from the well flow conductor to the lifting gas conductor. The gas lift valve may be removed while the crossover valve is in place in the crossover device, and the crossover flow control valve may be removed while the gas lift valve is in place in the crossover device, whereby each of said valves may be removed for servicing or repair, if desired, and the other valve remaining in place will prevent cross-flow of well fluids from the well flow conductor to the lifting gas conductor. A sliding sleeve valve may be incorporated in one or more of the longitudinal passages of the crossover device for positively closing the crossover flow passage when no crossover flow control valve or gas lift valve is in place in the crossover device. A method of operating a well having a plurality of parallel flow conductors extending thereinto by establishing communication between a pair of said flow conductors to permit flow of fluids downwardly through one of the conductors and across to the other and thence outwardly to the surface through said other conductor, to operate, install or remove well tools in said flow conductors and to establish desired circulation between formations in the well and the surface; or to provide gas lift for well fluids.

United States Patent Raulins 4 1 Aug. 1, 1972 [54] WELL TOOLS AND METHODS OF OPERATING A WELL [72] Inventor: George Max Raulins, Dallas, Tex.

[73] Assignee: Otis Engineering Corporation, Dallas, Tex.

[22] Filed: Aug. 20, 1970 21 Appl. No.: 65,425

Related US. Application Data [63] Continuation-in-part of Ser. No. 800,477, Feb.

7 Primary Examiner.lame's A. Leppink Attorney-E. Hastings Ackley 57 1 ABSTRACT Wellapparatus for use in a well having a plurality of flow conductors extending thereinto and providing a crossover flow conduit and valve means for controlling flow communication between a pair of said flow conductors to permit circulation of fluids from one of said conductors to the other of said conductors by means of said crossover conduit and valve means, to move well tools into and out of the well through one or the other of said flow conductors and to circulate fluids in the well to perform well service operations, for gas lifting or aerating the fluids in said other flow'conductor. A crossover device is connected between a pair of flow conductors for establishing fluid flow communication between the flow conductors. A crossover flow control valve is removably installed in a vertical flow passage concentric with one of the flow conductors for controlling flow of fluids from said conductor to the other through the crossover passage, operable by varying the pressure in one of the flow conductors, in the well bore or in a third flow conductor in the well, operable for admitting lifting gas to the other conductor for flowing the well fluids from the well producing formation upwardly out of the well through said other conductor. A gas lift valve is mountable and removably disposable in the other conductor in communication with the crossover passage for controlling the admission of lifting gas through the crossover flow passage into the well fluid conductor for controlling the lifting of the well fluids in said conductor to the surface. The crossover flow controlling valve may be omitted, if desired, and lifting gas admitted directly from the first conductor lifting gas conductor through the crossover passage to 2:55:24? am? aiv'e ti'aaa aos. a lfi illi from the well flow conductor to the lifting gas conductor. The gas lift valve may be removed while the crossover valve is in place in the crossover device, and the crossover flow control valve may be removed while the gas lift valve is in place in the crossover device, whereby each of said valves may be removed for servicing or repair, if desired, and the other valve remaining in place will prevent cross-flow of well fluids from the well flow conductor to the lifting gas conductor. A sliding sleeve valve may be incorporated in one or more of the longitudinal passages of the crossover device for positively closing the crossover flow passage when no crossover flow control valve or gas lift valve is in place in the crossover device. A method of operating a well having a plurality of parallel flow conductors extending thereinto by establishing communication between a pair of said flow conductors to permit flow of fluids downwardly through one of the conductors and across to the other and thence outwardly to the surface through said other conductor, to operate, install or remove well tools in said flow conductors and to establish desired circulation between formations in the well and the surface; or to provide gas lift for well fluids.

61 Clains, 29 Drawing Figures [151 3,680,637 451 Aug. 1, 1972 United States Patent Raulins PATENTEDAUB 1 I972 3,680. 6 37 sum 2 0F 8 I INVENTOR GM. RAULINS FIG-3 BY W ATTORNEY PATENTEDAUB 1 I972 3.680.637

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INVENTOR G.M. RAULINS ATTORNEY PATENTEB M19 1 2 sum 5 or a FIGQ- l6 INVENTOR GM. RAULINS FIG-l5 ATTORNEY PATENTEU 1 I972 SHEET 7 0F 8 ATTOF/VEY PATENTEDAus 1 I972 SHEET 8 [IF 8 INVENTOR. 6/14 Pow/)7:

TOFA/EV,

WELL TOOLS AND METHODS OF OPERATING A WELL This application is a continuation-in-part of my copending application, Ser. No. 800,477, filed Feb. 19, l 969.

This invention relates to well tools and a method of operating a well for controlling fluid flow between the surface and producing earth formations penetrated by the well, to flow control devices of a well installation, and to the method of operating a well having a plurality of parallel flow conductors extending thereinto and flow connected at a sub-surface point.

An important object of the invention is to provide an improved well tool for producing well fluids from earth formations penetrated by the well having a plurality of separate parallel flow conductors extending into the well and having means in the well below the surface thereof for establishing communication between a pair of said flow conductors to permit circulation of fluids downwardly through one conductor and upwardly in the other to provide for treatment of the flow conductors with fluids, to provide for movement of reciprocable well tools in the flow conductors, to provide for operation of well tools connected in the flow conductors by well tools movable through the flow conductors by fluid pressure, to provide for gas lifting well fluids in one or more of said plurality of flow conductors utilizing another flow conductor for conducting lifting gas into the well for injection through cross-flow valve means into said one or more conductors for lifting well fluids or oil in said one or more conductors.

Another object of the invention is to provide a well apparatus wherein the operation of the means for establishing communication between the flow conductors, or the crossover device, is responsive to fluid pressure in one of the flow conductors which is controllable from the surface of the well.

It is still another object of the invention to provide a well apparatus for establishing flow communication below the surface of the well between a pair of flow conductors in the well whereby well tools may be installed in and removed from the flow conductors by operator tools connectable to a transport train movable reciprocably in one or more of the flow conductors by the fluids circulated therein when the crossover device is open.

An important object of the invention is to provide a well apparatus comprising a crossover means connected to at least a pair of parallel flow conductors extending longitudinally into the well bore and providing a flow passage for establishing communication between said conductors at a point below the surface of the well and having valve means disposed therein for normally preventing cross flow of fluids from one of said conductors to the other of said conductors connected by said crossover means, said valve means being openable to establish communication between said flow conductors by fluid pressure in one of said flow conductors acting on said valve means and controlled from the surface of the well.

Still another object of the invention is to provide, in a well tool of the character described, valve means for controlling flow through the crossover flow conductor passage or conduit from one flow conductor to the other which is biased toward closed position to prevent such flow by biasing means associated with said valve means and normally-holding said valve means closed, and openable by fluid pressure from within one or the other of said flow conductors, and wherein said biasing means may comprise a fluid pressure charge confined within said valve means within a-chamber forming a part of said valve means, or fluid pressure from the annulus directed to said valve means and maintained out of communication with the fluids flowing through said flow conductors, or resilient means acting on said valve means, or a combination of said biasing means.

A further object of theinvention is to provide improved well tools and methods of operating wells having a'plurality of parallel side by side flow conductors therein and cross-flow passage means connecting each of said conductors with one or more of the other conductors at a subsurfacelocation in the well, wherein one of the flow conductors in the well is utilized as a lift gas conductor, and lifting gas from said one conductor is conducted through said cross-flow passage means to selected ones of the other conductors for lifting well fluids from the producing formations through such other flow conductors to the surface, and wherein a circulation control valve may be installed in the lifting gas conductor at said cross-flow passage means for ad mitting lifting gas from said liftinggas conductor into one or more of the other conductors for lifting the well fluids in said conductor or conductors, or wherein a gas lift valve may be installed in said other conductor or conductors at said cross-flow passage means for controlling admission of gas from the lifting gas conductor into the flow conductor in which the gas lift valve is installed for lifting the fluids, in such conductor, or wherein both a circulation flow valve'and a gas lift valve may be installed in the respective conductors to coact for controlling admission of gas from the lifting gas conductor into the well fluid conductor or conductors for lifting the well fluids from the well.

Another object of the invention is to provide well apparatus and methods of the character described wherein the valves may be installed in the respective strings by pumpdown, through flow line devices or by flexible line operating devices for installation of the flow controlling circulating valves and the gas lift valves in their respective flow conductors.

It is a particular object of the invention to provide, in a well having a plurality of parallel side by side flow conductors communicating with one or more producing formations in the well, means providing a crossover flow path from one of the flow conductors to the conductor or conductors communicating with the well producing formations, and valve means in said crossover flow passage device for controlling the admission of lifting gas from said one conductor into the other flow conductor or conductors for artificially lifting the well fluids or assisting flow of well fluids tothe surface from the producing formations, whereby the lifting gas is controlled in said one flow conductor and the well fluids are conducted to the surface through said other conductor or conductors by the lifting gas admitted thereto through the cross-flow path of the cross-flow device.

An important object of the invention is to provide an apparatus and method of the character described wherein means is provided for positively closing off all flow through the cross-flow passage, and wherein the method includes the step of positively separating the flow passages of the lift gas conductor and the well fluid conductor, when desired, to permit removal of the flow controlling circulation valve or the gas lift valve or both, if both are installed, for servicing, repair or any other purpose.

Still another object of the invention is to provide in a system and apparatus of the character described means for preventing flow of well fluids from the producing formation through the well fluid conductor and the cross-flow conductor into the lifting gas conductor.

Still another object of the invention is to provide flow controlling circulating valve means having structure which is not movable to open position by the pressure of fluids flowing from the otherconductor through the cross-flow passage into the flow conductor in which said circulating valve means is installed.

7 A particularly important object of the invention is to provide an apparatus for providing a cross-flow path between two flow conductors, wherein a receptacle is provided inlongitudinal alignment with the flow conductors having a bypass flow passage separate and spaced from the receptacle and a valve is disposed in said receptacle for controlling flow of fluid through the lateral or cross-flow passage from one conductor into the other conductor.

Additionalobjects and advantages of the invention willbe readily apparent from the reading of the following description of a device constructed in accordance withthe invention, and reference to the accompanying drawings thereof, wherein:

FIG. I is a schematic view, partly in elevation and partly in section, of a well installation embodying the invention and showing the crossover means connected in the well flow conductors for carrying out the inven-' tion;

FIG. 2 is a vertical section view of one form of the crossover means of the invention showing the same connected between apair of flow conductors and having a valve means disposed therein for controlling flow through said crossover flow passageway from said one of said flow conductors to the other;

FIG. 3 is a view similar to FIG. 2 showing the valve means in open position permitting flow between said conductors through said crossover passageway;

FIG. 4 is a view similar to FIG. 2 showing a modified form of crossover means having longitudinal flow passages which may be used for controlling circulation in either direction through said crossover means;

FIG. 5 is a vertical sectional view of a further modified form of the crossover means of the invention showing the same having a conduit for utilizing control fluid pressure in a separate conductor from the surface to control actuation of the circulation control valve;

FIG. 6 is a view similar to FIG. 5 showing still another form of crossover means with a sliding sleeve valve in one of the landing nipples for controlling fluid flow through the cross-flow passage of the crossover means;

FIG. 7 is a cross-sectional view taken on the line 7-7 of FIG. 2;

FIG. 8 is a horizontal cross-sectional view taken on the line 8-8 of FIG. 2.

FIG. '9 is a horizontal cross-sectional view taken on the line 9-9 of FIG. 4;

FIG. 10 is a horizontal cross-sectional view taken on the line 10-10 of FIG. 5;

FIG. 11 is a fragmentary vertical sectional view of a further modification of the crossover means;

FIG. 12 is a fragmentary view of still another fonn of the crossover means;

FIG. 13 is a fragmentary view similar to FIG. 12 showing sleeve valve means operable to close the crossflow passage when the valve is removed;

FIG. 14 is a fragmentary view of a well installation having the crossover means of FIG. 4 with valves installed in eachvertical passage;

FIG. 15 is a schematic view of a modified well installation embodying the invention; 7

FIG. 16 is a fragmentary vertical sectional view of a modified form of valve assembly having a bypass passage formed therein;

FIG. 17 is a fragmentary vertical sectional view of a valve assembly showing an auxiliary relief valve or shear plug incorporated therein;

FIG. 18 is a schematic view of a well installation showing a well installation for gas lifting;

FIG. 19 is an enlarged view, partly in elevation and partly in section, of an H-member cross-flow passage device, and a gas lift valve and circulation flow control valve disposed in the longitudinal passages of the device;

FIG. 20 is an enlarged fragmentary longitudinal sectional view of the gas lift valve utilized in the cross-flow device for controlling the admission of lifting gas from a lifting gas conductor into the well fluid eduction flow conductor;

FIG. 21 is a longitudinal sectional view, taken on the line 2l-21 of FIG. 22, showing a cross-flow passage device or H-member having a-pair of flow bypasses providing an enlarged bypass area through one of the longitudinal passages of the device;

FIG. 22 is a horizontal sectional view taken on the line 22-22 of FIG. 21; a

FIG. 23 is a horizontal cross-sectional view similar to FIG. 22 showing a modified form of the cross-flow passage device wherein a large bypass is connected in flow communication with one of the longitudinal flow passages of the cross-flow device and the other longitu? dinal flow passage is smaller than said one longitudinal flow passage;

FIG. 24 is a schematic view of a well flow conductor tively controlling the opening and closing of the crossflow passage;

FIG. 26 is a view similar to FIG. 24 showing a well in- FIG. 28 is a fragmentary longitudinal sectional view of a multiple cross-flow passage device having a circulating flow control valve mounted in the longitudinal bore communicating with the lifting gas conductor and controlling admission of lifting gas from said lifting gas conductor to the well fluid eduction conductors connected therewith through the lateral cross-flow passages and a gas lift valve in one of the other longitudinal passages communicating with the well fluid eduction conductors; and

FIG. 29 is a view similar to FIG. 27 showing a further modified form of multiple cross-flow passage device.

In the drawings, FIG. 1, well apparatus embodying the invention is shown schematically in a well having the usual well casing C which extends downwardly in the bore of the well to the lower end thereof and is provided with a plurality of sets of perforations 21 and 22 at its lower end establishing communication with the earth formations A and B surrounding the well bore and flowing through said perforations into the bore of the casing. The well installation includes a pair of parallel side by side strings of tubing or flow conductors 23 and 24, which extend downwardly from a casinghead H at the surface of the well sealing between the upper end of the casing C and each of the tubing strings or flow conductors. Valves 25 and 26 are provided in the flow conductors at the upper end thereof for controlling flow through the lateral flow wings 27 and 28, respectively. A lower packer or barrier 29 is located in the casing between the sets of perforations 21 and 22 and seals between the casing and the flow conductor 23, so that fluid flowing into the well bore through the perforations 22 will enter the lower end of the conductor 23, and flow upwardly therein. A dual packer or barrier 30 is located in the well casing above the upper set of perforations 21 and seals between the casing and each of the strings of tubing or flow conductors 23 and 24. The flow conductor 24 terminates below the dual packer 30 and above the lower packer 29 and fluids flowing into the bore of the casing through the upper set of perforations 21 will enter the opening at the lower open end of said tubing string 24 and flow upwardly therein. The packers, or barriers, may be of any suitable commercially available type which may be set either mechanically or hydraulically, as is well known to those skilled in the art. The casing above the upper packer 26 is usually filled in part with some loading fluid, such as water or mud, but the casing annulus may be open and have an operating fluid pressure therein for controlling actuation of the crossover means as will be hereinafter more fully described.

The well head H may include a lateral flow line or conductor 31 having a valve 32 connected therein for controlling entrance into and withdrawal of fluids from the annular space 33 between the tubing strings 23 and 24 in the casing above the packer 30. The pressure of fluids in the annular space may be controlled through the valve 32 in the usual manner.

The tubing string 23 has a landing nipple 35 connected therein below the lower packer 29, and a well tool 36, which is preferably a removable standing valve such as the valve shown in the 1966-1967 Composite Catalog of Oil Field Equipment and Services at page 3779, consisting of a back flow check valve releasably insertable into, lockable in, and removable from the landing nipple 35. A similar landing nipple 37 is connected to the lower end of the tubing string 24 and receives a check valve or a standing valve .38 similar to the valve 36 previously described. The check valves or standing valves 36 and 38 prevent back flow of fluids from the tubing strings or flow conductors into the producing formations through the perforations with which the open lower ends of the tubing strings communicate, but permit inward flow of fluids from said formations into the tubing strings and upwardly therein. If desired, other landing nipples and well tools may be connected at various vertically spaced elevations the tubing strings in the usual manner of operating and flowing a well, and, since the equipment is well known and is in common use by those skilled in the art, it will not be described in greater detail herein.

In order to pemiit installation and removal of the flow control devices in the tubing strings by means of a pump down train of tools (not shown), a crossover device or I-l-member assembly 40 is provided at a selected elevation in the well bore, being connected in the tubing string by usual screw threads at its upper and lower ends 51 and .52. The crossover device or II- member includes a bodyassembly=50 formed of a pair of landing nipples or body members 53 and 54 connected together by a transverse connector member and having a pair of laterally spaced "parallel longitudinal flow passages 53a and 54a formed therein. The landing nipple 53 having the threads 51 and 52 at its opposite ends is adapted to be connected to one of the flow conductors such as the tubing string 23 by means of said threads. The landing nipple 54 is similarly adapted to be connected by means of screw threads 51 and 52 to the tubing string 24so as to form a part thereof.

The transverse connector member 55 is connected to the two nipples 53 and-54 of the body 50 -by welds 56, or may be formed in any other suitable manner in an integral body having the flow passages cut longitudinally therein. The connector 55 is provided with a transverse connecting lateral cross-flow passage 57 communicating at its opposite ends with the bores 53a and 54a of the body, and provides for fluid flow between the flow conductors connected to said bores.

An external longitudinal bypass conductor 60 is mounted exteriorly of the body member 53 between a pair of opposed upper and lower bosses 61 and 62 which are secured as by welding to the exterior of said body member and provided with facing bores-6la and 62a, respective, which receive the tubular bypass conductor 60, said conductor being welded to the bosses in fluid tight relationship. Lateral ports 61b and 62b, respectively, connect the bores 61a and 620 with the bore 53a of the body member above and below the lateral connector 55 whereby fluids may flow through the bypass member in either direction into the bore of the body member above and below the connector member. A lateral flange 59 on the exterior of the body members 53 and 54 may be provided to form sufficient flat area for connecting the lateral connector 55 between the body members, and to support the midportion of the tubular longitudinal bypass conductor 60, if desired.

A circulation control valve assembly V is releasably mounted in the bore 53a of the body member 53 for controlling flow of fluids through the lateral connecting flow passage 57. The bores 53a and 54a of the body members 53 and 54 are formed with a plurality of locking recesses andysealing surfaces and stop shoulders therein for receiving the valve assembly, as will be hereinaftermore fully described. These recesses, shoulders and sealing surfaces are similar to the recesses to be found in the landing nipples illustrated in the Composite Catalog of Oil FieldEquipment and Services, l966-67 Edition, Pages 3,814 through 3,825. The grooves, shoulders and surfaces above the lateral flow eway resemble the Type E. or J landing nipple shown on Page 3,817, while the shoulders, recesses and surfaces below the lateral flow passage resemble the Type N or Q landing nipples on Page 3,816. Central enlargements 53b and 54b are formed in the bores of the bodymembers adjacent and communicating with the lateral flow e 57.

v The valve assembly V'is removably held in place in the bore of the body member 53 by a locking assembly 70, which may be of any desired type, but is schematicallyillustrat'ed as substantially the same as the Type X mandrel assembly shown on Page 3,815 of the aforesaid Composite CataloguThe locking assemblyhas a' locking mandrel 71 having dogs 7 1a which enter and engage in the annular locking recess 72 in the bore of the body member. A sealing assembly 73 engages and seals against the sealing surface 74 formed by the bore wall of the body member between the recesses 72 and 53b and prevents fluid flow upwardly through the body member exteriorly of the locking assembly. A knuckle joint assembly 75 is provided at the lower end of the mandrel 71 of the locking device 70 and receives a ball 76 threadedon the upper end of the mandrel 77 of the valve therebelow. The valve mandrel 77 is 81 engaging the seat 82 prevents back flow from the bore 540 ofthebody member 54 through the crossflow 1 anddownwardlyin'the bore 53a, and the ball .76 and the packing assembly 73 on-thelocking device 70 prevent upward flow in the bore-53a from the lateral passageway. I

When it B desired to open the lateral flow; passageway 57 to permit fluids to be circulated within the well through the tubing string to pump well tools upwardly or downwardly in said tubing strings or flow conductors, a suitably high fluid pressure is introduced into the bore ofthe tubing string or flow conductor 23,

bypass conductor so and through the 1mm] port 626 into the bore 530 of the body member below the valve assembly and into the tubing 23 therebelow. The pressure of the fluid acts on thecheck valve 36 at the lower end of the tubing string and is prevented from flowing outwardly through the lower end of the tubing string, so that the pressure builds up in the tubing string'23 below the valve V. When a sufficiently high pressure has been built up, such pressure will act upwardly on the ball valve closure member 81, moving the same upwardly against the charge of fluid pressure in the chamber 78 acting on the piston 80, and open the valve to flow upsection'83 of the valve mandrel. A packing assembly 84 g in the bore 53a above the lateral port 62b in the body member. The knuckle joint ball 76 closes the bore of the locking assembly 70 to prevent fluid flow upwardly or downwardly through the locking assembly, and pressure in the chamber 78 acting on the piston 80 biases the valve ball 81 downwardly against the seat 82 and closes the bore 83a of the lower valve mandrel packing section 83 to prevent flow therethrough. When the valve 81 is lifted off the seat 82, fluid from below the valve may flow upwardly through thebore 83a and outwardly throughlateral ports 87 in the mandrel 77 above the packing section 83 and upwardly through elongate longitudinal slotted flow courses 8 formed "exteriorly ofthe mandrel 77.*An external annular flange 89 is formed intermediate the ends of the manwardly through the bore 83a of the packing section to' the longitudinal flow courses 88 and upwardly to the lateral I flow passageway 57 and through such passageway into the bore 540 of thebody member 54 and the tubing string 24 connected therewith. With the pressure maintained at the elevated value which holds the valve open, fluid may be circulated in either direction at such elevated pressure through the two tubing strings and the lateral flow passageway. The check valves 36 and 38 prevent fluid pressure from escaping outwardly through the lower ends of the two tubing string 23 and 24.

It will be seen, therefore, that pump down well tools, such as are shown in the Composite Catalog heretofore mentioned at Pages 3,780 and 3,781, may be pumped upwardly or downwardly in either of the two tubing string 23 and 24 to perform varied operations. For ex ample, the equipment may be used to open a lateral between the two tubing string at'that elevation in the well, if desired.

Of course, other operations, such a swabbing opera tions, insertion and removal of other valves or flow controls in the body members 53 and 54 may be accomplished by such flow of fluids in the two tubing strings.

FIG. 3 shows the valve V in the open position permitting such flow of fluids from one string to the other through the crossover device.

FIG. 4 shows a crossover device a, identical to the crossover device 40 of FIGS. 2 and 3 with the exception that an additional longitudinal bypass tube or conductor 101 is provided on the exterior of the body member 540, being connected by means of bosses 102 and 103 having flow passages 102a and 103a therein communicating with lateral inlets or ports 102b and 103b which communicate with the bore 54d of the body member at points identical to the lateral inlets 61b and 62b of the body member 53. The body 40a of FIG. 4 permits installation of the control valve V in either of the body members 53 or 54c, since the members are identical in all respects. Thus, the control valve V may be inserted through either tubing string and landed in the crossover device to control cross flow, so that the control valve V may be inserted through the tubing 24 into the body member 540 of FIG. 4, or it may be positioned in the bore 53a of the body member 53, if desired.

A further modified form of the device is shown in FIG. 5, wherein the l-I-member or crossover device is similar in construction in all respects to the crossover device 40 of FIGS. 1 and 2, having landing nipples or body members 153 and 154 joined by a connector member 155 having a cross-flow passage 157 formed therein. However, in this modification, a lateral port 110 is formed in the upper portion of the bore 153a of the nipple 153 and a pipe connector sub 11] is welded, as at 112, in fluid tight relationship to the exterior of the nipple 153 and has a lateral port 113 and a longitudinal passage 114 communicating with the lateral port 110 in the landing nipple 153. The longitudinal passage 114 has a control fluid tubing string or conductor 115 threaded or otherwise connected to its upper end, whereby control fluid pressure may be introduced through the conductor 115, the passage 114 and the lateral ports 1 l3 and 110 into the bore 153a of the nipple 153. The valve V1 shown in this form of the device is identical in all respects to the valve V of the form first described, except that the mandrel 171 of the locking device has no longitudinal bore therethrough and its lower end is threaded into the upper end of a packing sleeve or mandrel 173 having external annular upper packing or sealing means 174 confined thereon by the locking mandrel and lower annular packing or sealing means 175 disposed exteriorly on the lower end thereof and confined thereon by a nut 172. The packing mandrel has a lateral port formed therein intermediate the sealing or packing assemblies and communicating with the bore 181 of said packing mandrel. The ball 176 at the upper end of the knuckle joint on the lower mandrel valve mandrel 117 is held in place in the bore of the packing mandrel by an internal sleeve threaded in the mandrel, and the upper reduced end of the bore 178 of the mandrel of the valve mandrel 117 opens into the bore of the packing mandrel and communicates with the lateral port 180 formed therein, whereby control fluid pressure from the tubular conductor 115 may be directed into the bore of the packing mandrel and into the bore of the valve mandrel 177 to act downwardly on the piston 80 of the valve to bias the ball closure member 81 thereof into sealing engagement with the seat 82 in the valve mandrel. The locking assembly 170 is otherwise identical to that of the form first described and will hold the valve V1 in place in the bore 153a of the landing nipple 153. It will be seen, therefore, that in this form of the crossover device, the valve Vl may be operated to control flow of fluids from one of the landing nipples 153 and 154 to the other by means of control fluid pressure conducted into the bore of the valve mandrel through the control fluid conductor 115.

In this form of the device, therefore, the actuation of the valve may be controlled from the surface of the well, rather than being controlled by a dome charge of pressure as in the chamber 78 of the form first described.

In other respects, the valve functions and is operated in the same manner as the valve and crossover device of the form first described.

In FIG. 6, a further modified form of the I-I-member or crossover device 240 is shown, wherein a modified valve V2 biased closed by a spring 278a in the chamber 278 is positioned in the landing nipple 253, and the landing nipple 254 is provided with a sliding sleeve valve structure in its bore 254a for further controlling flow through the crossover passage or cross-flow passage 257. The bore of the landing nipple 254 is enlarged in its central portion 254b to provide an elongate longitudinal cylindrical recess in which a sliding sleeve valve member 260 is slidable longitudinally. Upper and lower sections of the landing nipple are 35 joined by threads 255 to permit installation of the sleeve in the bore 254b. The threaded joint may be welded as at 255a, if desired, after insertion of the sleeve. This sleeve is slidable between an upper shoulder 261 and a lower shoulder 262 in the bore 254b and upper seal means 263 and lower seal means 264 provided in suitable annular recesses in the bore 254b above and below the cross-flow passage 257 seal against the exterior of the sleeve to prevent fluid flow therepast, whereby when the sleeve is in the position shown in FIG. 6 the cross-flow passage 257 is closed off to flow in either direction. The sleeve 260 is movable downwardly until its lower end engages the lower shoulder 262, in which position a plurality of longitudinally extending lateral flow openings or slots 265 formed in the upper portion of the sleeve are disposed in registry with the cross-flow passage 257 and fluids may flow through the openings 265 in either direction through the cross-flow passage 257. The upper O-ring seal means seals against the exterior of the sleeve above the openings 265 when the sleeve is in the lower position. Other than the provision of the sliding sleeve valve in the bore of the landing nipple 254, the crossover device 240 is identical to that of the device of FIG. 2 already described, and will function in the same manner when the sleeve 260 is in the lower position in which the openings 265 are registered with the cross-flow passage 257 to permit flow in either direction through such cross-flow passage. Of course, when the sleeve is in the upper position shown in FIG. 6, the cross-flow passage 257 is closed and the fluids cannot be circulated through the cross-flow passage.

A further modified form of the I-I-member or crossover device 340 is shown in FIG. 1 1, wherein the landing nipple 353 is provided with a sliding sleeve valve 360 in its bore communicating with a lateral port 310 formed in the wall of the landing nipple above the cross-flow 1 g 357. The sliding sleeve valve is similar 'to the sleeve valve'shown in FIG. 6, but has a longer length above the lateral openings 365. A plurality of spherical locking balls 320 are disposed in lateral openings 321 formed in the wall of the sleeve adjacent its upper end. The balls are confined against displacement by-the inwardly tapered walls of the lateral opening, which permit the balls to project or protrude into the bored the sleeve, but prevent the balls from escaping from the lateral openings. The locking device 370 is provided with an external annular recess 330 into which the balls are adapted to project and be locked in projecting position upon downward of the sleeve in the bore of the landing nipple. A stop shoulder 331 is formed on the exterior of the locking device 370 below the annular recess 330 and engages an upwardly facing shoulder 332 formedin the fore of the sliding sleeve of the, sleeve valve wherebydownward movement of the locking device causes downward movement of the sleeve valve from anrupper position in which the balls are disposed in an internal annular locking recess 323 in thebore of the landing nipple 353, whereby the balls will be moved in the lateral openings 321 into the annular recess 330 topermit the sleeve valve to be moved downwardly. The upper end of the sleeve valve 360 is beveled to engage an internal annular inwardly and upwardly inclined stop shoulder 334 at the upper end of the enlarged bore 353b in which the sleeve is slidable.

. When the locking device is disposed with the shoulder 331 on the locking device engaged with the upwardly facing stop shoulder 332 in the valve sleeve, further downward movement of the locking device will move the sleeve downwardly and the engagement of the balls with the beveled shoulder at the lower end of the annuwhich the valve sleeve is slidable. The dogs are then expanded into locking position wherein they engage the shoulder 334 and hold the sleeve downwardly in its lower position in the bore 353b and the valve assembly V3 locked in place in the landing nipple. A helical coiled spring 325 is disposed in the enlarged bore 353b below the lower end of the valve sleeve 360 and en- 7 gages the shoulder 362 at the lower end of the enlarged bore and the lower end of the sleeve 360 to bias the sleeve upwardly toward the upper closed position. The

"lateral flow passages 365in the valve sleeve are in communication with the lateral flow port 310 in the mandrel 353 when the sleeve is in the lower position shown in FIG. 1 l, and fluids may enter through the port 310 of the mandrel and pass through the openings 365 in the sleeve ,to enter through the lateral ports 380 in the packing mandrel 3730f the locking device, whereby fluids directed inwardly throughthe lateral port 310 will control actuation of the valve V3.

Upward movement of the mandrel alter the dogs closed position after the balls have been moved into the recess 323 in the landing nipple 353 and the locking device and valve V2 have been withdrawn from the bore of the crossover device.

The port 310 may be connected to a control fluid conduit such as is shown in FIG. 5, or the port may merely communicate with the exterior of the landing nipple 353, whereby fluid pressure within the annulus between the well casing and the tubing strings may enter through the lateral port 310 and act on the piston of the valve 81 to control opening and closing of the valve. Such casing fluid pressure may be controlled by means of the valve 32 at the upper end of the well to control actuation of the valve V3.

A still further modification of the H-member, or crossover device 440 is shown in FIG. 12 wherein the shoulder 331 on the locking device 370 engages the upper end of the valve sleeve 460 to move it downward, and the spring 325 of FIG. 11 is omitted and the lower end of the valve sleeve shoulders directly against the upward facing shoulder 462 at at the lower end of the enlarged bore 453b to limit downward movement of the valve sleeve in the nipple 453. Upward movement of the valve sleeve 460 in this form of the device is limited by the engagement of the dogs 3710 of the locking device 370 with the shoulder 434 at the upper end of the enlarged bore 453b'. The dogs 371a lock the mandrel in the lower position and hold the valve sleeve in the lower open position with the lateral openings 465 in communication with the lateral ports 410 in the landing nipple 453. The'balls 420 in the valve sleeve function in the manner already described to enable the locking device to move the valve sleeve upwardly and to release the locking device from the valve sleeve.

Other than repositioning the shoulder 331, shortening the length of the annular recess 453b in which the sliding valve sleeve 460 slides, and omitting the spring I 325, this form of the device is identical to the fonn of FIG. 11.

Obviously, the sleeve valve may be installed in either of the landing nipples 453 and 454 of the device, if desired, and the proper valve assembly may be inserted into the landing nipple of the tubing string from which it is desired to control circulation of fluids between the two tubing strings.

It is also desired that, in some cases, a sleeve valve 660 similar to the sleeve 460 of FIG. 12 be formed with a longer lower portion 661 and lateral flow opening or port means 662 similar to the flow openings or ports 265 of FIG. 6, so that when the pressure responsive flow control valve assembly V4 is installed inthe sleeve 660 and the sleeve is moved downwardly to the position shown in FIG. 13, the lateral .opening or port means 666 will be disposed in registry with the crossflow passage 657, and the lateral port 665 in the sleeve will be in registry with the control fluid lateral port 610 in the landing nipple 653. It is readily apparent that when the sleeve valve 660 and the flow control valve assembly V4 are disposed in such position, the valve assembly V4 will control flow through the cross-flow passage 657 in the same manner as the valve assemblies of the forms already described.

The elongate sliding sleeve valve 660 is slidable in an elongate enlarged bore 653b in the landing nipple 653 between the upwardly facing stop shoulder 662 at the lower end and the shoulder 434 at the upper end of such enlarged bore. The external annular downwardly facing shoulder 431 on the locking device 370 of the valve engages the upper end of the valve sleeve to move the sleeve downwardly to engage the stop shoulder 662. Other parts of the sliding sleeve and valve assembly are identical to and function in the same manner as those of FIG. 12 and are given the same identifying numerals. Therefore, when the valve assembly V4 is removed, the sliding sleeve 660 is moved upwardly in the bore 653b until the upper end of the sleeve engages the shoulder 434 and the imperforate po portions of the sliding sleeve close the control fluid inlet lateral port 610 and the cross-flow passage 657 so that there is no communication of flow through such port or passage while the valve is not disposed in the landing nipple.

Obviously, if desired, the control fluid lateral port 665 may be omitted and a valve assembly such as the assemblies V or V2 may be used to control flow through the cross-flow passage, being responsive to fluid pressure in the tubing string 23 rather than control fluid pressure from the surface or from the casing annulus.

In FIG. 14 the crossover device or I-I-member assembly 40a of FIG. 4 is shown as having a valve assembly V in each of the landing nipples. Such installation provides for positive separation of the well fluids flowing through the tubing strings 23 and 24 in the event of failure of either one of the valve assemblies, so that if one valve assembly should fail to function, as by loss of pressure charge in the chamber 78 of the valve assembly, the other valve assembly can function to control flow through the cross-flow passage. Each of the valves may be opened by elevating the fluid pressure in the tubing string connected to the vertical passage or bore of the landing nipple in which the valve is disposed, in the manner already described with respect to the devices of FIGS. 1 through 4.

It is also believed readily apparent that more than two strings of tubing may be installed in a well, as shown in FIG. 15, wherein three tubing strings 523, 524 and 525 are illustrated, each having a multiple H- member or crossover device 540 connected therewith. The landing nipples 553 and 554 of the two outer tubing strings 523 and 524, respectively, include the longitudinal bypass conductors 560 and 601, respectively, while the central landing nipple 551 need not have a longitudinal bypass conductor. Cross connectors 555a and 555b are provided connecting the two outer landing nipples 553 and 554 with the central landing nipple 551, and valves may be installed in either of the outer landing nipples to control flow between the tubing strings to which the outer landing nipples are connected and the central tubing string in either direction.

Obviously, also, the fluid may be conducted from the central tubing string into either or both of the lateral tubing strings, if desired, after the valves located in the outer landing nipples are opened and the pressure in the tubing strings is maintained at a sufficiently elevated value.

The installations of FIGS. 1, 14 and 15 are also adaptable to completion procedures in which no casing is installed in the well and a plurality of tubing strings are cemented or otherwise sealed within the well bore communicating with the producing zones of the well. Of course, the form of the crossover device of FIGS. 1 1 and 12 and 13 would require a separate control fluid line or conductor such as that shown in FIG. 5. Otherwise, the valves would function in the manner previously described.

A further modification of the device is illustrated in FIG. 16, wherein the removable flow control means or valve means V5 is provided with a longitudinal bypass flow passage 701 therethrough opening into the bore 54a of a landing nipple, such as the landing nipple 54 of the crossover means 40 of FIG. 2, above and below the valve means V5 when it is disposed in said landing nipple, so that flow of fluids may take place through such longitudinal passage 701 at all times.

The valve closure means 781 controlling flow between the bore 54a of the landing nipple 54 through the cross-flow passage 57 and the bore 53a of the otherlanding nipple 53 is disposed in a longitudinal opening or passage 702 formed in the body 777 of the valve means to one side of the longitudinal by-pass flow passage 701 and having a lateral opening 704 between the seal assemblies 773 and 784 communicating with the cross-flow passage 57 of the crossover means 40.

A pressure charge chamber 705 is formed in the body 777 of the valve means V5 above the closure means 781 and the piston 780 of the closure means is slidable in the bore 702 below the lower end of the bore 778 of the charge chamber and is biased by the charge in the chamber to yieldably hold the closure means against the replacement valve seat 782 in the enlarged threaded lower end 702a of the bore 702.

The valve closure means 781 will function exactly as those of the previous forms of the device, being opened by fluid pressure in the bore 54a of the landing nipple 54 to permit fluids to flow through the cross-flow passage 57 in either direction.

This form of the device provides a removable by-pass passage carried by the removable valve means V5. It eliminates the necessity for an external by-pass on the landing nipple as shown in the FIGS. 2, 5, 6 and 12. Of course, the valve V5 may be installed in the bore of any of the landing nipples not having a lateral control fluid port, such as the ports 110, 310, and 410, to control flow of fluid through the cross-flow passage of the crossover means.

To assure being able to open the valve closure member 81 of the valve assembly, in the event the bypass passage in the landing nipple or in the removable valve assembly should become closed in any manner so that fluid pressure could not be transmitted through such by-pass passage to act on the valve closure member to open the same to establish flow through the cross-flow passage 57, an auxiliary relief valve or shear plug is provided in the locking mandrel of the valve assembly, as shown in FIG. 17.

The relief valve or shear plug comprises a disc 90 having an external annular shear flange 91 formed integrally therewith and projecting circumferentially therefrom to provide a shear member of predetermined thickness and strength. The shear flange is confined between a shoulder 92 in the bore of the bushing or sub 93 which is threaded onto the lower end of the packing or seal mandrel 94 of the valve V. The flange is confined between the shoulder 92 and the lower end of the mandrel in fluid-tight sealing relationship therewith by means of the threaded connection between the sub or bushing and the mandrel, which permits the mandrel and sub to telescope to the extent necessary to effect such sealing engagement. A lateral port 95 is provided in the wall of the bushing 93 above the knuckle joint member 75 and the upper end of the ball member 76 on the upper end of the mandrel of the valve therebelow.

It will be seen, therefore, that fluid pressure present in the bore 53b of the landing nipple 53 above the valve assemblymay enter through the lateral port 95 and act on the under side of the disc 90. If the pressure is sufficiently great, the flange 91 will be sheared and the fluids may pass in either direction through the bore 70a of the locking mandrel, the lateral port 95 and the cross-flow passage 57-of the crossover means.

If desired, of course, fluid pressure in the bore 54a of the landing nipple 54 above the valve assembly may be applied downwardly through the bore 700 of the locking mandrel to act on the upper surface of the disc 90 to force the same downwardly in the bore of the bushing 93 to shear the shear flange 91 and permit circulation downwardly through the bore of the locking mandrel and outwardly through the lateral port 95 to the bore 53b, and through the cross-flow passage 57 into the bore 53b of the landing nipple 53 of the crossover means. g

This relief valve structure provides a secondary means for establishingflow between the two tubing strings and the bores of the two landing nipples in the event the by-pass passageways 60 and/or 701 should become clogged or closed for any reason so as to prevent actuation of the valve in the usual manner, or if for'any other reason the valve will not open or cannot be opened. The pressure at which the shear flange 91 on the disc is sheared is chosen to be a valve substantially above that required for normal operation of the valve closure member 81 to move the valve closure to open position. For example, if the valve closure is set to .be opened at 1,000 psi. differential acting on the valve, the shear flange could be designed to fail at a pressure differential of 2,000 p.s.i., so that elevation of the pressure in either of the tubing strings to a valve resulting in a 2,000 psi. or greater differential would shear the flange and open the passage to flow. This structure will therefore assure the ability to establish circulation between the tubing strings at the crossover means, in the event the valve should not be openable in the usual manner, to permit circulation of fluids and actuation of tools in the tubing strings.

From the foregoing, it will be seen that an improved well tool and method of operating a well has been provided in which fluid flow between the surface and the producing earthformations may be controlled from the surface by actuation of a crossover fluid flow circulating valve disposed in a crossover device connected between the tubing strings. Also, fluids may be flowed through the tubing strings in either direction after opening of the valve in the manner set forth.

It is also believed readily apparent that improv valve means has been provided for controlling flow through the tubing strings and through the cross-flow passage in response to fluid pressure in the flow conductors or tubing strings. The valve closure means may be controlled by a dome pressure confined in the valve means, by a spring confined within the valve means and acting on the same, or by a fluid pressure from the surface of from a source exterior to the crossover device, and by fluid pressure in the annulus between the casing and the tubing.

It can further be seen that the device is particularly adapted for use in pump-down type well installations wherein a transport train of tools is flowed into and out of the flow conductors or tubing strings in the well by fluids circulated through the flow conductors.

It will also be seen that the crossover device includes means for normally preventing cross-flow of fluids from one of the conductors to the other, which is openable to establish communication when desired, and that means has been provided for closing off flow of control fluid from the surface to the valve and to close off the flow of control fluid from exteriorly of the crossover device to the valve.

In FIG. 18, a well installationsimilar to that of FIG; 1 but particularly adapted for gas lifting a single zone is schematically shown. The usual well casing C has perforations 21 at its lower end establishing communication with the earth formation below'the usual packer 29 anchored in the well casing and sealing between one of two flow conductors or tubing strings 23 and 24 and the casing. The strings of tubing 23 and 24 extend downwardly through a casing head H at the surface of the well sealing between casing C and each of the tubing strings. Valves 25 and 26 are connected to the tubing strings above the casing head for controlling flow out of the well. The surface tubing string23a extends to a separator S which has a gas vent 27 at its upper end communicating with a valve 28 leading to a gas disposal line 28a or flare or other place of disposal of the gas, and an oppositely directed conductor 27a leading to a compressor C driven by a motor M which is connected to the surface tubing string 24a. The liquid discharge line 29 from the separator leads to a storage tank S having a surface flow line 29a connected thereto and having a valve 29b for controlling flow from the tank through the flow line. If desired, a lateral flow line 31 having a valve 32 therein may be connected to the easing below the casing head H for controlling flow of fluids into and out of the casing in the annular space therein between the tubing strings 23 and 24.

A plurality of cross-flow devices or H-members such such as are illustrated in FIG. 4 are connected to the tubing strings 23 and 24 at a plurality of elevations in the well. Each H-member (FIG. 19) has a longitudinal bore 53a communicating with the tubing string 23 and a separate laterally spaced longitudinal bore 54a communicating with the tubing string 24. The cross-flow member 55 having the cross-flow passage 57 therein connects the landing nipple or leg 53 of the H-member to the landing nipple or leg 54 and provides a flow path communicating the bores of the landing nipples.

Each of the cross-flow devices or l-l-members 40a has an external longitudinal by-pass conductor 60 and 101 mounted exteriorly of the landing nipples 53 and 54c, respectively, of the body member, whereby fluids may flow through the by-pass member in either direction into the bore of the landing nipples 53 and 540 above and below the cross-flow connector member 55.

A circulation control valve assembly V6 is releasably mounted in the bore 54a of the landing nipple 54c for controlling flow of fluids through the lateral flow passage 57 into the bore 53a of the landing nipple 53.

The valve assembly V6 is substantially identical to those valve assemblies previously described but does not have the knuckle joint 75. The valve is removably held in place in the bore of the landing nipple 540 by a locking assembly 70, of the type shown in FIGS. 2 and 16, having the locking dogs 71a engaged in the annular locking recess 72 and the upper sealing assembly 73 sealing against the sealing surface formed by the bore wall of the landing nipple between the locking recess 63 and the enlarged central bore 54b, and the lower packing assembly 84 sealing against the sealing surface formed by the.bore wall of the landing nipple between the enlarged central bore 54b and the lateral port 103b to the by-pass conductor 101 to prevent fluid flow exteriorly of the mandrel in the bore 54a above the lateral port l03b. Pressure in the valve chamber 78 acts on the piston 80 to bias the valve ball 81 downwardly against the seat 82 and closes the bore 83a of the valve mandrel lower packing section 83 to prevent flow therethrough. When the ball valve 81 is lifted off the seat 82, fluid from below the valve may flow upwardly through the bore 83a and outwardly through the lateral ports 87 in the valve mandrel into the enlarged bore 54b of the landing nipple and through the cross-flow bore 57 of the cross-flow connector member 55 into the bore 53a of the landing nipple 53, where it will flow either upwardly or downwardly in the tubing string or flow conductor 24 connected therewith. The ball valve 81 prevents backflow from the bore of the landing nipple 53 through the cross-flow passage 57 and inwardly through the lateral ports 87 in the valve mandrel past the ball valve, and downwardly and outwardly into the bore 54a of the landing nipple. Similarly, the upper packing assembly 73 and the lower packing assembly 84 prevent flow in the bore 54a in either direction from the lateral flow passageway 57 exteriorly of the valve assembly in the landing nipple.

Should it be desired to admit lifting fluid or gas from the tubing string 23 through the valve V6 into the bore of the landing nipple 53 and into the tubing string 24 to lift well fluids therein, the pressure of the lifting gas present in the bore of the tubing string 24 is elevated by means of the compressor C to a desired degree, and such high pressure lifting fluid will flow downwardly through the tubing string 24 and the by-pass conductor 101 into the bore 54a of the landing nipple 54c below the valve assembly. The check valve 38 at the lower end of the tubing string 24 will prevent escape of the lifting fluid out the open lower end of the tubing string and will direct the gas upwardly to act against the ball valve 81 to move the same upwardly against the pressure charge in the chamber 78 to unseat the valve and permit the lifting fluid gas to pass between the ball valve and the seat 82 and thence outwardly through the lateral ports 87 in the 'valve mandrel into the bore of the landing nipple 540 between the upper packing assembly 73 and the lower packing assembly 84, where it will be directed through the lateral flow passage 57 into the bore of the landing nipple 53 to aerate and lift the column of well fluids present in the tubing string 23 to the surface, either by slugging the same or by continuous aeration and lightening of the entire column above the lateral port. The admission of the lifting fluids into the tubing string 23 in this manner may be done intermittently or continuously to provide the slugging or the continuous'flow type gas lifting of the fluids.

In such an installation, a gas lift valve need not be installed in the bore of the landing nipple53.

However, if desired, and in many cases it is much more desirable, a gas lift valve G of the type shown in the Pat. to Canalizo, No. 2,954,043, issued Sept. 27, 1960, or in the US. Pat. to Canalizo, No. 3,375,846, issued Apr. 2, 1968, may be releasably anchored in the bore 530 of the landing nipple 53 for controlling the admission of the lifting fluid or gas into the tubing string 23 in a more efficientand precise manner.

The gas lift valve G includes a locking mandrel 500 having expansible and retractable latch means or dogs 501 similar to the locking assembly of the valve assembly V6. The expansible and retractable locking dogs 501 are adapted to engage in the internal annular locking recess 72a in the bore of the mandrel 53 to support the gas lift valve in the landing nipple against movement in either direction therein. The locking mandrel also carries below the locking dogs 501 an annular seal assembly 502 which is disposed to seal against the sealing surface provided by the bore of the landing nipple between the lockingrecess 72a and the enlarged central bore 53b adjacent the cross-flow passage 57. Below the sealingassembly the valve mandrel 503 extends downwardly to a point below the lateral cross-flow passage 57 and has a check valve mandrel 505 threaded into the lower end of its bore. A lower external annular packing assembly 506 is mounted on the check valve'mandrel 505 and is held in place thereon by a guide and flow cap 507 threaded onto the lower reduced end of the check valve mandrel 505. The sealing assembly 506 seals against a sealing surface formed by the bore wall of the landingnipple between the lateral flow passage 57 and the lateral bypass port 62b. Gas inlet ports 504 are formed in the wall of the valve mandrel 503 between the upper packing 502 and the lower packing 106. Thus, lifting gas entering the bore 53a of the landing nipple 42 through the lateral flow course or passage 57 will be confined'in the bore of the landing nipple between the upper packing 502 and the lower packing 506 and enter through the ports 504 into the valve mandrel. The annular enlarged bore 440 facilitates passage of the lifting gas in the bore of the landing nipple .to the lateral ports 504 in the valve mandrel.

A tubular valve support 508 is disposed in the bore of the mandrel 503 of the valve and has its lower end closed as at 509 and lateral ports 510 formed in its side walls above the closed lower end 509 whereby a charge 512 which has its upper end 513 bonded or otherwise suitably secured to the exterior of the tubular supporting member 508 above an external annular shoulder 514 formed thereon. An O-ring 515 seals between the tubular supporting and the bore of the valve mandrel 503. A retainer or support member 516 having a concave upper surface 517 is supported on the upper end of the tubular check valve mandrel 505. A plurality of circumferentially spaced longitudinal slots 518 are formed in the outer surface of the retainer and provide passages for the flow of fluids therepast. The cup-like valve sleeve or closure member 512 is closed at its lower end and is constructed of resilient material such as rubber, Neoprene or other elastomeric material, or the like. The outer surface of the closed lower end of the valve sleeve approximates a hemisphere and is supported on the concave surface 517 of the support member and confined between such concave surface and the hemispherical lower end 509 of the tubular support member 508. The charge of gas in the charge chamber 511 acts through the ports 510 on the interior surface of the valve sleeve 512 to bias the same outwardly and into engagement with the bore wall of the valve mandrel 503-from above to below the lateral ports 504 in said mandrel, whereby when the sleeve is in the expanded position engaging the bore wall of the mandrel the lateral ports 504 are closed. When pressure exteriorly of the mandrel is sufficiently high, the sleeve will be deformed and deflected away from the bore wall of the mandrel 503 and open the passages 504 to permit gas to flow inwardly through the passages and downwardly in the bore of the mandrel 503 through the longitudinal slots 518 in the support member and downwardly into the bore of the check valve mandrel 505.

A check valve 519 is threaded into the upper end of the bore 505a of the check valve mandrel, and includes acheck valve bodyor spider 520 having a cup shaped opening 521 in its lower end. A tubular cup-like resilient check valve seal element 530 constructed of rubber, Neoprene or other elastomeric material, or the like, has an outwardly inclined lip 531 as its lower end normally resiliently engaging the bore wall 505a of the mandrel 505. The seal element or cup 530 is secured in the cup shaped opening in the check valve body by a cap screw 532 threaded into said body with its head engaging an inwardly extending annular flange 533 at the upper end of said element. A resilient tubular reinforcing sleeve 534 having a plurality of depending fingers 535 is disposed around the check valve element within the cup shaped opening of the check valve body whereby the element is reinforced by the fingers of said sleeve. The fingers are adapted to overlie the lower ends of a plurality of longitudinally extending slots or flow passageways 536 formed in the exterior surface of the check valve body or spider 520 to prevent extrusion of the resilient sealing cup 530 outwardly in the slots by pressure from below. The bore 505a of the mandrel opens into the bore 507a of the guide and flow cap 507 and a plurality of laterally spaced longitudinal flow passages 537 open from the. interior of the cap to the spider 520 and the check valve seal member 530 may pass outwardly through the longitudinal openings 537 into the bore of the landing nipple for aerating liquids from the well formation A present in the tubing string 23 to cause the same to flow outwardly through the lateral ports 62b upwardly through the by-pass conduit to the upper lateral ports 614 where they flow inwardly into the bore of the landing nipple above the gas lift valve and thence upwardly through the tubing string 23 to the surface.

This type of gas lift valve provides for continuous or intermittent injection of lifting gas into the tubing string 23 to aerate the column of liquids present in the strings to cause the same to flow to the surface. If desired, a gas lift valve of the type shown in the US. Pat. to Canalizo, No. 3,375,846, may be installed rather than the valve G previously described to provide a regulated flow of lifting gas into the tubing string 23 from the lifting gas tubing string 24. The valve G thus permits intermittent flow, as well as continuous flow, of lifting gas from'the lifting gas string into the production string to aerate or slug the column of fluids present in the tubing string 23 to cause the same to be moved to the surface, as is usual in gas lift operations. The other valve of Canalizo, US. Pat. No. 3,375,846, is adapted for continuous regulated admission of gas into a column of liquids or other fluids flowing upwardly in the tubing string 23 to economically and efficiently produce the liquids to the surface.

As the well fluids are lifted to the surface, they will flow upwardly past the valve 25 through the lateral surface flow line 23a to the separator S, where the liquids will be separated from the gases, and the liquids will pass through the conduit 29 to the storage tank T, from whence they may be withdrawn through the conduit 29a controlled by the valve 2% for disposal in a suitable manner. The gases separated from the liquids in the separator will flow outwardly through the exhaust conduit 27 at the upper end of the separator to a valve 28 and a surface flow line 280 leading to a flare, or surface lines or other points of disposal of the gas so produced from the producing formation and separated from the liquid. In carrying out the gas lift operation, a gas conduit 27a is connected to the exhaust conduit 27 from the separator, and gas separated from the fluids at the separator, or from the gas line 28a, will be conducted through the conduit 27a to a compressor C driven by a motor M for compression to a higher pressure for injection through the surface flow line 24a past the valve 26 into the lifting gas tubing string 24 to be conducted downwardly into the well to the cross-flow devices or H-members 40a for use in gas lifting the fluids from the producing formation 21 in the well.

It will be noted that the check valve 519 prevents back flow of liquids from the producing string 23 through the gas lift valve G to the cross-flow passage 57 and into the lifting gas conduit 24. This check valve 519 of the gas lifi valve functions to prevent such back flow, as does the ball valve 81 of the cross-flow regulating valve V6. Also, the check valve 519 permits removal of the cross-flow regulating valve V6 fro servicing, repair or replacement, when desired, without admitting the producing well fluids from the producing formation to pass from the tubing string 23 through the lateral flow port passage 57 to the lifting gas tubing string. 

1. A method of operating a well penetrating a plurality of spaced fluid producing earth formations, and having a plurality of flow conductors in the well in position to communicate with the producing earth formations, barrier means between producing earth formations closing the well about said flow conductors extending therethrough, one of said flow conductors communicating with each of said producing earth formations at its lower end and being sealed off from said other producing earth formations by said barrier means, and crossover means connecting said flow conductors and operable in response to fluid pressure change in one of a pair of said flow conductors for establishing flow communication between said pair of said flow conductors, said method including: increasing the fluid pressure in said one of said pair of flow conductors to operate said crossover means to establish fluid flow communication between said pair of flow conductors in said well above the locations of communication of said flow conductors with the separate producing earth formations; and circulating fluids through said flow conductors through said crossover means downwardly from and upwardly to the surface through said flow conductors after said crossover means has been moved to open position.
 2. The method of claim 1, and including: separating said producing earth formations from said circulating fluids during circulation of said fluids through said pair of flow conductors.
 3. The method of claim 1, and including: closing said pair of flow conductors between the locations of their communication with the producing earth formations and said crossover means during circulation of fluids through said pair of flow conductors and said crossover means.
 4. The method of claim 1, and including: closing off flow between said pair of flow conductors through said crossover means and flowing said well fluids from said producing flow earth formations through said flow conductors separately.
 5. The method of claim 3, including: testing the crossover means when it is in closed position by increasing the pressure in one of said pair of flow conductors while said pair of flow conductors are closed below the crossover means, and determining at the surface whether fluid flow is taking place from one of said flow conductors of said pair into the other flow conductor of said pair.
 6. Apparatus for operating a well including: a plurality of flow conductors in said well bore; crossover flow control means connecting the lower portions of at least two of said flow conductors and including fluid pressure responsive Means for directing flow of fluid from said well into one of said two flow conductors; means in one of said two flow conductors for shutting off flow from said well into said one flow conductor; and means for establishing fluid communication between said one of said two flow conductors and the other of said two flow conductors and for circulating fluid therethrough.
 7. Apparatus for operating a well traversing a plurality of subsurface producing formations vertically separated from each other, including: a first flow conductor extending into said well to a point adjacent the upper subsurface producing formation; a second flow conductor extending into said well to a point adjacent the next lower subsurface producing formation; crossover flow control means interconnecting said first flow conductor and said second flow conductor; barrier means directing the flow of fluid from the upper producing subsurface formation through said first flow conductor and directing the flow of fluid from the next lower producing subsurface formation through said second flow conductor; and means for closing off flow from said producing formations through said flow conductors and operable by fluid pressure in at least one of said first and second flow conductors for establishing circulation between said flow conductors through said crossover means.
 8. Apparatus of the character set forth in claim 7 wherein said barrier means comprises: upper packer means in said well sealing about said first and second flow conductors and above the upper subsurface producing formation; and lower packer means in said well sealing about said second flow conductor and between the upper and next lower subsurface producing formations.
 9. Crossover flow control meaNs for a well having a plurality of flow conductors extending into said well for producing well fluids therethrough, said crossover flow control means including: body means having a plurality of separate longitudinal flow passages therethrough, one connectable to each of said flow conductors, said body means also having cross-flow passage means formed therein communicating each of said flow conductors with another one of said flow conductors; and valve means in one of said longitudinal flow passages of said crossover flow control means movable between open and closed positions for preventing fluid communication between one of said flow conductors and the other flow conductor with which it is connected in flow communication by said cross-flow passage means when in closed position and movable to open position by fluid pressure in at least one of said one and another communicating flow conductors to establish flow communication through said cross-flow passage between said one and another flow conductors with which said cross-flow passage is connected.
 10. The crossover flow control means of claim 8 wherein: said means for controlling flow through said cross-flow passage comprises valve means exposed to and actuated by fluid pressure from within at least one of said pair of flow conductors between which said cross passage communicates for establishing flow communication through said cross-flow passage.
 11. Crossover flow control means for a well having a plurality of flow conductors extending into said well for producing well fluids therethrough, said crossover flow control means including: body means having a plurality of separate longitudinal flow passages therethrough, one connectable to each of said flow conductors, said body means also having cross-flow passage means formed therein communicating each of said flow conductors with another one of said flow conductors; valve means in said crossover flow control means movable between open and closed positions for preventing fluid communication between one of said flow conductors and the other flow conductor with which it is connected in flow communication by said cross-flow passage means when in closed position and movable to open position by fluid pressure in at least one of said one and another cOmmunicating flow conductors to establish flow communication through said cross-flow passage between said one and another flow conductors with which said cross-flow passage is connected; said means for controlling flow through said cross-flow passage being removably insertable into and removable from said crossover flow control means through one of said communicating flow conductors.
 12. Crossover flow control means for a well having a plurality of flow conductors extending into said well for producing well fluids therethrough, said crossover flow control means including: body means having a plurality of separate longitudinal flow passages therethrough, one connectable to each of said flow conductors, said body means also having cross-flow passage means formed therein communicating each of said flow conductors with another one of said flow conductors; flow control valve assembly means in one of said longitudinal passages having means for sealing with said body means in said longitudinal flow passage above and below said cross-flow passage means, said valve assembly means having a flow passage therein communicating with said cross-flow passage means; valve closure means in said valve assembly means controlling flow through said flow passage of said valve assembly means and normally biased to closed position for shutting off flow through said flow passage to prevent flow from said longitudinal passage through said cross-flow passage means, said valve closure means being exposed to and responsive to fluid pressure in one of said longitudinal passages of said body means for actuation to an open position to permit cross-flow from said longitudinal passage through said cross-flow passage means to the other longitudinal passage with which said cross-flow passage means communicates.
 13. An apparatus of the character set forth in claim 12 wherein said means for biasing said valve closure means to closed position comprises a closed chamber having a fluid pressure charge therein acting on said valve closure means to bias said valve closure means to closed position.
 14. A device of the character set forth in claim 12 wherein said biasing means comprises a resilient means.
 15. An apparatus of the character set forth in claim 12 wherein said biasing means comprises means conducting fluid pressure from the surface of the well.
 16. An apparatus of the character set forth in claim 12 wherein said biasing means comprises means conducting fluid pressure from externally of said body means in said well.
 17. An apparatus of the character set forth in claim 12 wherein said crossover flow control means includes: fluid bypass passage means communicating with said one of said longitudinal flow passages of said body means above and below the point of communication of said cross-flow passage means with said longitudinal passage.
 18. A crossover flow control means of the character set forth in claim 12 wherein said body means includes: a plurality of separate longitudinal bypass flow passages each communicating with one of the longitudinal flow passages through said body above and below the point of communication of said cross-flow passage means with said longitudinal flow passage.
 19. An apparatus of the character set forth in claim 12 wherein a sliding sleeve valve means is provided in one of said longitudinal flow passages movable between a position closing said cross-flow passage means communicating with said longitudinal flow passage and a position opening said cross-flow passage means to permit flow therethrough from and to said longitudinal flow passage.
 20. Apparatus of the character set forth in claim 17 wherein said body means is provided with a flow conductor opening into said longitudinal flow passage between the points of communication of said bypass passage means with said longitudinal passage for conducting control fluid pressure to said longitudinal flow passage to bias said valve means in said longitudinal flow passage toward closed position.
 21. Apparatus of the character set forth in claim 17 wherein said crossover flow control body means is provided with a lateral port between the points of communication of said bypass passage with the longitudinal flow passage, and sleeve valve means is provided in said longitudinal flow passage for opening and closing said lateral port to control flow into and out of said longitudinal passage through said lateral port.
 22. Apparatus for operating a well having a plurality of well flow conductors extending thereinto for producing well fluids from said well, including: crossover flow control means having a plurality of separate longitudinal flow passages therethrough, one connectable to each of said flow conductors, said crossover flow control means also having a plurality of cross-flow passage means formed therein each communicating one of said longitudinal flow passages with another one of said longitudinal flow passages; valve means in said crossover flow control means movable between open and closed positions for controlling flow through said cross-flow passage means between said communicating longitudinal flow passages for preventing fluid communication between said longitudinal flow passages through said cross-flow passage means when said valve means is in closed position and permitting flow through said cross-flow passage means when said valve means in in open position; means biasing said valve means toward closed position; said valve means being movable to open position by fluid pressure in one of said longitudinal flow passages; and means in each of said longitudinal flow conductors preventing back flow between said crossover flow control means and the point of communication of said flow conductors with said well fluids.
 23. Apparatus for operating a well in which a plurality of well tubing strings are disposed in said well communicating with said well at their lower ends which comprises: a crossover flow control means connecting said tubing strings to each other, said crossover flow control means having a first cross-flow passage means providing cross-flow communication between one of said tubing strings and a second tubing string, and having a second cross-flow passage means providing cross-flow communication between said second tubing string and a third tubing string, each of said cross-flow control valve means having means for receiving a cross-flow control valve means; and cross-flow valve means releasably anchored in at least one of said cross-flow passage means and having means biasing said valve means to position closing off-flow through said cross-flow passage means between the two tubing strings having cross-flow communication through said cross-flow passage means; said valve means having means exposed to and operable by fluid pressure in one of said communicating tubing for movement of said valve means to open position to permit flow through said cross-flow passage means by imposition of a predetermined controlled fluid pressure in said one of said tubing strings.
 24. An apparatus of the character set forth in claim 23 wherein: means is provided in said flow tubing strings for preventing back flow of fluids from said tubing strings to said well between said crossover flow control means and the point of communication of said tubing strings with said well.
 25. An apparatus of the character set forth in claim 21 wherein said sleeve valve means is engaged by said valve means for moving said sleeve valve means to open position when said valve is installed in said sleeve valve means.
 26. An apparatus of the character set forth in claim 25 including: locking means carried by the sleeve valve means; means of said valve means engageable by said locking means of said sleeve valve means when said valve means is inserted in said sleeve valve means for moving said sleeve valve means to its closed position when said valve means is removed from said sleeve valve means.
 27. An apparatus of the character set forth in claim 22 wherein valve means is disposed in each of said sEparate longitudinal flow passages of said crossover flow control means, said valve means each preventing flow through said cross-flow passage means when said valve means is closed and permitting flow through said cross-flow passage means when said valve means is in open position.
 28. A device of the character set forth in claim 12, wherein the valve closure means is moved to open position in response to only the pressure in the longitudinal passage in which said valve is installed.
 29. A device of the character set forth in claim 12, wherein the valve closure means is moved to open position in response to only the pressure in the longitudinal passage in which said valve is installed, said valve being disposed to be maintained is said open position by fluid pressure present in either of the two longitudinal passages communicating with said crossover means in excess of the pressure required to move the valve closure means to open position.
 30. A device of the character set forth in claim 12, wherein by-pass passage means is provided in said crossover means communicating the longitudinal flow passage in which said valve means is disposed above and below said flow control valve means to provide a path of flow past said flow control valve means at all times.
 31. A crossover flow control means of the character set forth in claim 12, wherein a fluid flow by-pass passage is provided in said flow control means spaced from said flow passage communicating with said cross-flow passage whereby fluid may flow through said flow control means past said valve closure means to the longitudinal flow passage above and velow said flow control means at all times.
 32. A crossover means of the character set forth in claim 12 wherein: relief valve means is provided in said valve assembly means openable at an elevated pressure above the pressure normally required to open the valve closure means to provide a passage through the valve assembly for circulation of fluids therepast through the cross-flow passage of the crossover means.
 33. A cross-flow device for intercommunicating a plurality of separate well flow conductors within a well bore comprising: body means having a plurality of separate longitudinal flow passages therein and having means for connecting each of said flow passages with a separate well flow conductor; means in said body means providing a separate cross-flow passage between said longitudinal flow passages; and bypass passage means in said body means communicating with one of said longitudinal flow passages on longitudinally opposite sides of the cross-flow passage communicating therewith.
 34. A cross-flow device of the character set forth in claim 33 wherein valve means is provided in said body movable therein for selectively closing off flow through the cross-flow passage communicating with said longitudinal flow passage having the by-pass communicating therewith.
 35. A cross-flow device for intercommunicating a plurality of separate well flow conductors with a well bore comprising: body means having a plurality of separate longitudinal flow passages therein and having means for connecting each of said flow passages with a separate well flow conductor; means in said body member providing a separate cross-flow passage between pairs of said longitudinal flow passages; and a plurality of separate by-pass passage means in said body means each communicating with a separate one of said longitudinal flow passages on longitudinally opposite sides of the cross-flow passage communicating therewith.
 36. A cross-flow device for intercommunicating two or more of a plurality of well flow conductors comprising: a body having a plurality of longitudinal flow passages therein having means for connecting each of said flow passages to a well flow conductor; means in said body providing a cross-flow passage between one of said longitudinal flow passages and each of the other longitudinal flow passages of said body; valve means in said body movable for selectively closing off flow through each of said cross-flow passages; and bypass passage means in said body communicating with one of said longitudinal flow passages on longitudinally opposite sides of the cross-flow passage communicating therewith.
 37. A cross-flow device for intercommunicating a plurality of separate well flow conductors within a well bore comprising: body means having a plurality of separate longitudinal flow passages therein and having means for connecting each of said flow passages with a separate well flow conductor; means in said body means providing a separate cross-flow passage between pairs of said longitudinal flow passages; by-pass passage means in said body means communicating with one of said longitudinal flow passages on longitudinally opposite sides of the cross-flow passage communicating therewith; and longitudinally movable valve means having a lateral opening therein disposed in one of said longitudinal flow passages and movable between a position closing said transverse flow passage communicating with said longitudinal flow passage to isolate said longitudinal flow passage and a position in which said lateral opening is disposed to flow communication with said longitudinal flow passage through said transverse flow passage.
 38. A cross-flow device for intercommunicating two or more of a plurality of well flow conductors comprising: a body having a plurality of longitudinal flow passages therein having means for connecting each of said flow passages to a well flow conductor; means in said body providing a cross-flow passage between one of said longitudinal flow passages and each of the other longitudinal flow passages of said body; valve means in said body movable for selectively closing off flow through each of said cross flow passages; and a plurality of separate bypass passage means in said body each communicating with a separate one of said longitudinal flow passages on longitudinally opposite sides of the cross-flow passage communicating therewith.
 39. A cross-flow device of the character set forth in claim 33 including: a sliding sleeve having a lateral opening therein disposed in one of said longitudinal flow passages of said body means, said sleeve being movable longitudinally between one position in which said longitudinal flow passage is in flow communication with the one of the longitudinal passages communicating therewith through said cross-flow passage and another position in which said longitudinal flow passages are isolated from each other.
 40. A cross-flow device for intercommunicating two or more of at least three well flow conductors comprising: a body having at least three separate longitudinal flow passages therein and having means for connecting each of said flow passages with a separate well flow conductor; means in said body providing a separate cross-flow passage between the longitudinal flow passages of pairs of said longitudinal flow passages of said body; and valve means in said body movable therein for selectively closing off flow through each and all of said cross-flow passages.
 41. A cross-flow device of the character set forth in claim 40 including by-pass passage means on said body communicating with one of said longitudinal flow passages on longitudinally opposite sides of the cross-flow passage communicating therewith.
 42. A cross-flow device for intercommunicating two or more of at least three well flow conductors comprising: a body having at least three separate longitudinal flow passages therein and having means for connecting each of said flow passages with a separate well flow conductor; means in said body providing a separate cross-flow passage between one of said longitudinal flow passages and each of the other longitudinal flow passages of said body; and valve means in said body movable therein for selectively closing off flow through each and all of said cross-flow passages.
 43. A cross-flow device of the character set forth in claim 42 wherein said valve means in said body movable for selectively closinG off flow through each of said cross-flow passages is located in said one flow passage.
 44. A cross-flow device for intercommunicating two or more of a plurality of separate well flow conductors comprising: a body having a plurality of separate longitudinal flow passages therein having means for connecting each of said flow passages to a separate well flow conductor; means in said body providing a cross-flow passage between one of said longitudinal flow passages and each of the other longitudinal flow passages of said body; and a plurality of by-pass passage means on said body communicating with each of said other longitudinal flow passages in said body on opposite sides of the cross-flow passage communicating with said other longitudinal flow passages.
 45. A cross-flow device of the character set forth in claim 1 including: means on said valve means engageable with a well tool movable into said one flow passage through the well flow conductor connected therewith for moving said valve means between positions opening and closing said cross-flow passage.
 46. A cross-flow device of the character set forth in claim 45 including: locking recess means in the longitudinal passage having said valve means therein spaced from said valve means when said valve means is moved to opened position engageable by said well tool after said valve means has been moved to open position to hold said well tool in place in said passage.
 47. Apparatus of the character set forth in claim 23 wherein the tubing string with which said cross-flow control valve means is connected in flow communication is a lifting gas conductor, and said cross-flow control valve means is opened by the pressure of the lifting gas in said lifting gas conductor tubing string to admit lifting gas through said cross-flow passage means between said lifting gas conductor tubing string and one or more of said other tubing strings, for lifting the well fluids in said other tubing string or strings.
 48. Apparatus for operating a well of the character set forth in claim 22 wherein one of said valve means is a gas lift valve.
 49. Crossover flow control means of the character set forth in claim 12 wherein said flow control valve assembly means is a gas lift valve.
 50. Crossover flow control means of the character set forth in claim 12 wherein the longitudinal flow passage in which said flow control valve assembly means is located is connected with a lifting gas supply tubing string, and said flow control valve assembly means is operable by the pressure of the lifting gas in said tubing string acting on said valve to admit such lifting gas through said cross-flow passage means in controlled amounts into the other of said longitudinal passages with which said cross-flow passage means is connected for lifting well fluids in the tubing string connected with such other longitudinal passage.
 51. Crossover flow control means of the character set forth in claim 50 wherein a gas lift valve is disposed in said other longitudinal passage for operation by the lifting gas crossing thereto through said cross-flow passage means from said lifting gas tubing string.
 52. Crossover flow control means of the character set forth in claim 9, wherein said valve means is a gas lift valve.
 53. Crossover flow control means of the character set forth in claim 9 wherein a gas lift valve is disposed in the other of the longitudinal passages with which the cross-flow passage means from said one longitudinal flow passage is connected.
 54. A cross-flow device of the character set forth in claim 33 including: a gas lift valve disposed in one of said longitudinal flow passages communicating with the cross-flow passage communicating with said longitudinal passage for controlling admission of lifting gas through said cross-flow passage.
 55. A cross-flow device of the character set forth in claim 33 including: a gas lift valve disposed in the one of said longitudinal passages having the by-pass flow passage communicating therewith for Controlling admission of lifting gas through the cross-flow passage into said longitudinal passage and by-pass passage.
 56. A cross-flow device of the character set forth in claim 33 including: a gas lift valve disposed in the longitudinal flow passage with which the cross-flow passage from the longitudinal passage having the by-pass flow passage communicating therewith is connected.
 57. A cross-flow device of the character set forth in claim 33 including: cross-flow control valve means in the longitudinal passage having the by-pass flow passage communicating therewith and operable by pressure in said longitudinal passage and by-pass flow passage to permit flow therefrom through the cross-flow passage to the other longitudinal flow passage with which said cross-flow passage is connected in flow communication.
 58. A cross-flow device of the character set forth in claim 33 including: cross-flow control valve means in the longitudinal passage having the by-pass flow passage communicating therewith and operable by pressure in said longitudinal passage and by-pass flow passage to permit flow therefrom through the cross-flow passage to the other longitudinal flow passage with which said cross-flow passage is connected in flow communication; and a gas lift valve disposed in said other longitudinal flow passage and operable by fluid pressure in said cross-flow passage.
 59. A cross-flow device of the character set forth in claim 57 including: longitudinally movable valve means having a lateral opening therein disposed in one of said longitudinal flow passages communicating with said cross-flow passage and movable between a position closing said cross-flow passage and a position in which said cross-flow passage is open to permit flow therethrough.
 60. A cross-flow device of the character set forth in claim 58 including: longitudinally movable valve means having a lateral opening therein disposed in one of said longitudinal flow passages communicating with said cross-flow passage and movable between a position closing said cross-flow passage and a position in which said cross-flow passage is open to permit flow therethrough.
 61. A cross-flow device for intercommunicating two or more of at least three well flow conductors comprising: a body having at least three separate longitudinal flow passages therein and having means for connecting each of said flow passages with a separate well flow conductor; means in said body providing a separate cross-flow passage between each pair of said longitudinal flow passages of said body; valve means in said body movable therein for selectively closing off flow through each of said cross-flow passages; and by-pass passage means on said body communicating with one of said longitudinal flow passages on longitudinally opposite sides of the cross-flow passage communicating therewith. 